Orion Moon Filter 1.25-inch 25% Transmission
|Orion moon filters improve contrast and make lunar observing more comfortable and enjoyable. |
Observing the moon with a telescope, especially a large telescope, can be a lot like shining a flashlight in your eye. Moon filters reduce the light transmission but are color neutral. We recommend a 25% filter for telescope smaller than 4 inches of aperture and a 13% filter for telescopes larger than 5 inches in aperture. Either filter will work well between four and five inches of aperture. Users of very large telescopes may also find a 25% transmission moon filter useful for observing the brighter planets.
We are able to see the Moon at night thanks to sunlight reflecting off its rocky surface. When looking at the Moon through a telescope, bright reflected sunlight can produce significant glare. The Moon's disk, even at partial phases, is in fact so intensely bright with reflected sunlight that observing surface details can be challenging due to the overwhelming glare. This glare can be so bright that it washes out most of the interesting lunar features such as craters, rilles, mountains, and valleys. The considerable brightness also reduces contrast on our nearest neighbor in the solar system.
When the Moon is in its crescent phase, it does not produce as much glare as when it is full or waxing, but filtration is still recommended to achieve optimal view quality. When looking at the Moon in relatively small (60mm-80mm) telescopes, the brightness is not as distracting as in larger telescopes, but some filtration is required to get the best observations. To improve contrast and tone down glare easily in these situations, we recommend using a neutral-density 1.25" Orion 25% Transmission Moon Filter. This inexpensive accessory threads directly into a 1.25" eyepiece barrel and blocks 75% of the light gathered by the telescope, making for more comfortable lunar views exhibiting higher contrast. Once installed on a 1.25" telescope eyepiece, the Orion 25% Transmission Moon Filter will bring out considerably more lunar surface details thanks to the boosted contrast. Not only will more surface features and details pop out, but you can study them in greater comfort, thanks to Moon Filter reducing overall brightness without altering color. This neutral-density telescope eyepiece filter reduces irradiation, which is the distortion at the boundary between light and dark areas, such as along the lunar terminator. Using a Moon filter also helps conserve dark-adapted vision while viewing the lunar surface.
The Moon is one of the most interesting objects in the night sky to observe through a telescope. Its rugged surface is a feast for the eyes of amateur astronomers, with fascinating craters, mountainous highlands, and large, dark lunar "seas" formed by ancient volcanic activity. Night after night, the Moon is a treasure-trove of visual adventures for astronomers of all skill levels. With a 1.25" Orion 25% Transmission Moon Filter you can affordably enhance all your views of Earth's natural satellite.